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The burgeoning issue of landfill leachate, exacerbated by urbanization, necessitates evaluating its biological impact, traditionally overshadowed by physical and chemical assessments. This study harnesses Caenorhabditis elegans, a model organism, to elucidate the physiological toxicity of landfill leachate subjected to different treatment processes: nanofiltration reverse osmosis tail water (NFRO), membrane bioreactor (MBR), and raw leachate (RAW). Our investigation focuses on the modulation of sugar metabolism, particularly trehalose—a disaccharide serving dual functions as an energy source and an anti-adversity molecule in invertebrates. Upon exposure, C. elegans showcased a 60–70% reduction in glucose and glycogen levels alongside a significant trehalose increase, highlighting an adaptive response to environmental stress by augmenting trehalose synthesis. Notably, trehalose-related genes in the NFRO group were up-regulated, contrasting with the MBR and RAW groups, where trehalose synthesis genes outpaced decomposition genes by 20–30 times. These findings suggest that C. elegans predominantly counters landfill leachate-induced stress through trehalose accumulation. This research not only provides insights into the differential impact of leachate treatment methods on C. elegans but also proposes a molecular framework for assessing the environmental repercussions of landfill leachate, contributing to the development of novel strategies for pollution mitigation and environmental preservation. [ABSTRACT FROM AUTHOR]

Extensive studies have shown that the relationship between flooding duration and wetland plant biomass is context specific. The underlying mechanisms, however, are uncertain. A likely explanation is that flooding has both direct effects by exerting stress on plants and indirect effects by affecting soil nutrient availability. The net effect would be context‐specific and might depend on season. Here, we tested two potential factors mediating the flooding effects on wetland plant biomass: soil nutrient availability and season.We carried out a field investigation in the lakeshore meadows of the Poyang Lake floodplain, China, along a flooding duration gradient during the non‐flooding period. To test the interaction between flooding duration and soil nutrients, we carried out a nutrient (N and P) addition experiment in two types of communities with different flooding durations.The above‐ground biomass (AGB) decreased with flooding duration in winter but had a quadratic response in spring, suggesting that the direct negative effect of flooding was stronger in winter than in spring. Soil total N content, total P content, and N:P ratio showed quadratic responses to flooding duration.Our results supported the hypotheses that the influence of nutrient limitation decreased with flooding duration and was greater in spring than in winter. The evidence showed that, with longer flooding duration and in winter than in spring, the correlations between AGB and soil nutrient content were weaker, leaf N and P content of Carex cinerascens were stronger, and AGB response ratio to nutrient addition was lower. Meanwhile, the relative importance of N versus P to wetland plant biomass varied with flooding duration.Consequently, indirect effects of flooding duration on AGB via soil nutrient availability were much less important than direct effects in winter or with long flooding duration, but were more important in spring or with short flooding duration. Therefore, the effects of flooding on wetland plant biomass depended on flooding duration, soil nutrient availability, and season. [ABSTRACT FROM AUTHOR]

Aims Plant community assembly in wetlands usually changes with elevation gradients, which may be due to the direct effect of flooding and indirect effects such as changes in soil properties and competition. However, the respective importance of each factor remains to be investigated. Methods We investigated patterns of plant diversity, community biomass and soil properties along an elevation gradient of a lakeshore meadow at Poyang Lake, China. Important Findings (i) With increasing elevation, species richness and Simpson diversity index decreased. Both aboveground biomass (AGB) and belowground biomass (BGB) increased with elevation, however, the BGB/AGB ratio also increased, which suggests a significant effect of belowground competition. (ii) Soil N content and soil N:P ratio increased, whereas soil pH decreased with elevation. Other soil properties showed no significant response. (iii) Structural equation modeling showed that variation of plant diversity was mainly explained by BGB. Thus, intensified belowground competition seems to be the primary mechanism causing lower plant diversity at higher elevations. (iv) These findings were further supported by the observed greater response ratio of N and P storage in plant communities than the response ratio of soil N and P content to elevation, suggesting that soil nutrient limitation and belowground nutrient competition increased with elevation. Our study has important implications to wetland management and biodiversity conservation under environmental change (e.g. changes in flooding regimes, eutrophication). [ABSTRACT FROM AUTHOR]

The first complete mitochondrial genome (mitogenome) of Cerithioidea (Gastropoda: Caenogastropoda) was determined using a freshwater snailSemisulcospira libertina(Cerithioidea: Semisulcospiridae) as a representative species of the superfamily. The mitogenome was 15,432 bp in length, including 13 typical invertebrate protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. The overall base composition was 31.4% for A, 17.8% for C, 34.8% for T and 16.0% for G with a A + T bias. The mitogenome ofS. libertinadisplayed novel gene order arrangement compared with published Caenogastropoda mitogenomes to date. This mitogenome contributed in resolving phylogenetic position and interrelationships of Cerithioidea. [ABSTRACT FROM PUBLISHER]